Method for verifying a clamp-on ultrasonic measuring device

Abstract

A method for verifying a clamp-on ultrasonic measurement device, wherein the measurement device comprises: at least two ultrasonic transducers configured to transmit and receive ultrasonic signals; and an electronic measuring/operating circuit configured to operate the ultrasonic transducers, to provide measured values of a measured variable, and to perform the verification, wherein the electronic measuring/operating circuit has a memory, the method comprising: mounting the measurement device on a standard measuring section; switching on a verification mode of the electronic measuring/operating circuit; transmitting an ultrasonic signal with at least one ultrasonic transducer and receiving the ultrasonic signal with at least one ultrasonic transducer; detecting a measured value of a verification variable of the ultrasonic signal and comparing the measured value with a specification value, stored in the memory, of the verification variable; outputting a verification result; and terminating the verification mode.

The invention claimed is: 
     
         1 . A method for verifying a clamp-on ultrasonic measurement device, wherein the measurement device comprises:
 at least two ultrasonic transducers configured to transmit and receive ultrasonic signals; and   an electronic measuring/operating circuit configured to operate the at least two ultrasonic transducers, to determine measured values of at least one measured variable, and to perform the verification, wherein the electronic measuring/operating circuit includes a memory unit,   the method comprising:
 mounting the measurement device on a standard measuring section, wherein the standard measuring section is a measuring block or a measuring rod; 
 activating a verification mode of the electronic measuring/operating circuit; 
 transmitting at least one ultrasonic signal with an ultrasonic transducer of the at least two ultrasonic transducers; 
 subsequently receiving the ultrasonic signal with another ultrasonic transducer of the at least two ultrasonic transducers; 
 determining at least one measured value of at least one verification variable of the ultrasonic signal; 
 comparing the at least one measured value with at least one specification value, stored in the memory unit, of the at least one verification variable; 
 outputting a verification result based on the comparing of the at least one measured value with the at least one specification value; and 
 deactivating the verification mode. 
   
     
     
         2 . The method of  claim 1 , wherein the at least one verification variable is one of:
 a signal amplitude of a received ultrasonic signal;   a signal transit time of an ultrasonic signal;   a sonic velocity;   a runtime difference of two ultrasonic signals that are transmitted and received in pairs by the at least two ultrasonic transducers without the presence of a flowing medium in the standard measuring section;   a signal-to-noise ratio;   a signal form given by a rise time, fall time, amplitude or frequency; and   a correlation between a received ultrasonic signal and an expected ultrasonic signal.   
     
     
         3 . The method of  claim 1 , wherein the standard measuring section is made of at least one of: plastic and metal. 
     
     
         4 . The method of  claim 1 , wherein the verification result comprises a profile of measured values with respect to a specification variable. 
     
     
         5 . The method of  claim 1 , wherein the verification result includes a prediction with respect to an operating time until a new verification of the measurement device is to be performed. 
     
     
         6 . A clamp-on ultrasonic measurement device configured to implement the method according to  claim 1 , the measuring device comprising:
 at least two ultrasonic transducers configured to transmit and receive ultrasonic signals, the at least two ultrasonic transducers mounted or mountable on a measuring tube;   an electronic measuring/operating circuit configured to operate the at least two ultrasonic transducers, to determine measured values of at least one measured variable, and to perform the verification,   wherein the electronic measuring/operating circuit includes a memory unit in which at least one specification value is stored.   
     
     
         7 . The method of  claim 5 , wherein the prediction is based on an evaluation of the at least one verification variable relative to limit values of associated target ranges of the at least one verification variable.